Process of making ammonia and compounds thereof.



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H. W. LAMB.

PROCESS OF MAKXEVG AMMONIA AND CGMPOUNDS THEREOF.

APPLICATION FILED SEPT. 17. 1913.

1,207,567. Patented Dec. 5,1916.

2 SHEETS-SHEET 1.

INVENTOR A TTORNE Y 1,207,567. Patented Dec. 5,1916.

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PROCESS OF MAKING AMMONIA AND COMPOUNDS THEREOF. APPLICATION m n snnnyms.

Y. a a g a? z 2 g "a! VI z I/Z nv VEN TOR A TTORNE Y HENRY WHITING LAMB, OF LEOI'tISMIOU'JZH, VIRGINIA.

PROCESS OF MAKING AMMONIA AND COMPOUNDS THEREOF.

Specification of Letters Patent.

Patented Dec. 5, 1916.

Application filed September 17, 1913. Serial No. 790,18.

To all whom it may concern Be it known that I, HENRY WHITING LAMB, a. citizen of the United States, residing at Portsmouth, in the county of Norfolk and State of Virginia, have invented certain new and useful Improvements in Processes of Making Ammonia and Compounds Thereof, of which the following is a specification.

This invention relates to. the fixation of atmospheric. nitrogen and formation of ammonia, and has for its object the utilization of the varying aflinity of solid metal carbid for nitrogen under varying temperatures, for securing nitrogen from its gaseous state and delivering it to hydrogen in the formation of ammonia at thermal points of attraction and expulsion in a progressively alternating and continuous manner, whereby ammoniamay be yielded and secured from its elements by the catalytic or contact action of solid metal carbids on free nitrogen and hydrogen actuated byheat broadly, and specifically, by internal heat induced by electrical resistance of the" metal carbid to electrical currents and more" specifically t0 electrical currents of varying density, the operation being preferably augmented by exposing thegaseous agents, viz. nitrogen and hydroge n, to chemical change, transformation or union While under super-atmospheric pressure.

In carrying out the process it is preferred to employ an apparatus of the character illustrated in the accompanying drawings to which attention. is directed in connection 'with the description of the various process steps as hereinafter set forth, in which' Figure 1 is a longitudinal vertical section of a converter adapted to be'actuated by electricity, and Fig. 2 is a transverse vertical section in perspective of the same on line 22, Fig. 1, Fig. 3 is a side elevation bf a modified form of apparatus employing combustion heat, and Fig. '4 is a cross-sectionon line 51-4, Fig. 3.

Similar numerals of reference indicate correspondingparts in the several views. Referring to Figs. 1 'and- 2, the numeral 1 represents a closed metal shell provided with a lining 2.; The shell 1 is provided with a cover 3, and heat shield 24, secured thereto by the bolts 4 passing through the flanges. 5 in suitable air-tight manner. The interior of the apparatus isprovided with an arched or bridged Wall 6 provided with perforations or openings 7. At either end of the appathe conductors and electrical attachments 10 and 11. Extending between the said electrical contacts: 8 and 9 are graphite rods or conductors of small diameter 12 adapted to act as electrical leadsbetw'eenthe points of contact and initial heaters of the metal carbid 13, surrounding the same in the apparatus. On either side of the apparatus is provided a multiplicity or plurality of inlets 14 and 15 communicating with thebonduits 16 and 17 and provided with the regulating valves 18 and 19 through which is supplied the nitrogen and hydrogen respectively to the interior of the apparatus in a suitably controlled manner. The apparatus is provided with an outlet 20, provided with an adjustable pressure and relief valve 21, adapted to retain the gases in the apparatus against a fixed and adjustable pressure and to provide for the discharge of the products I manner in which the same is performed or carried out, the production of ammonia. from atmospheric nitrogen, and hydrogen will be taken. I

Calcium carbid, in a pulverized or finely ground condition, isplaced in the oven or furnace and is subjected to the alternate action of nitrogen and hydrogen. The carbid composes a contact substance or a catalytic mass which possesses the property. of absorbing, combining, retaining or '00- eluding nitrogen or hydrogen when in. a

heated state, and of delivering the hydrogen or nitrogen to themitgnogen j or "hydrogen,

as the case may be, at a. different temperature, at which temperature the carbon has. superior aflinity for the metal base ofthe carbid than has the nitrogen or hydrogen. The operation is continued without destroyingthe physical -or chemical character or contact properties of the carbid thereby enabling the carbid to be used repeatedly by merely regenerating the-carbid tothe active state, alternating the nitrogen and hydrogen, and maintainin the .carbid at thermal points where its alhnity for nitrogen increases or diminishes While the nitrogen and hydrogen are supplied thereto in the 1701 600 C., and the carbid will continue to ab so'rb and to liberate nitrogen hydrogen at such temperature in the formation of ammonia, as long as the nitrogen and hydrogen are alternately supplied thereto, it being preferable to supply the nitrogen and by drogen at a pressure of one ormore atmospheres. In practice, it is preferable to run the furnace in such a Way that the nitrogen and hydrogen are alternately supplied for periods of one hour each, ammonia being liberated continuously.

The nitrogen is preferably recovered from the air -or'atmosphere by passing it over heated copper or other substance capable of combining with or removing the oxygen while the h" drogen is produced. by the do oxidation 0 water or steam by the action of heated coplper, iron or other -metal having.

superior a nity for ox gen, or with carbon producing water gas mm which is elimi nated the, carbon monoxid or carbon dioxid or both byI'an'y well knownmeans.

other carbid of solid nature than calcium may be employed such as iron, titanium, magnesium,'barium, etc.-, capable of taking on nitrogen and delivering it to hydrogen, either individually or collectively, or the carbid employed maybe associated with other solid inert vehicles or carriers for the pur ose of rendering available as large a sur ace to the action of the gases as possible,

without departing from the spirit of the invention. The hydrogen employed may be secured from a source foreign to'the carbid .-'catalytic substance or can be produced in 50 association therewith by decomposition of Water in .the. presence thereof, in 'forin of steam, superheated steam, or otherwise.

The transformation of nitrogen through the "mediation of solid metal carbid into a form or condition nascent in character capable of uniting with hydrogen may be augmented by superatmospheric pressure or carried out under any practical or available condition with reference to the energy employed as to direct heat or induced by electricity as well as under ordinary atmos' pheric pressure or other conditions.

It will he noted that in cases where electricity is employed as a means for inducing heat through the internal resistance of the Any carbid catalytic or contact material that the temperature can be controlled and regulated at will and with great facility and in cases where the material is in granulated form or character the points of contact presenting less cross section of conductive material becomes superheated, or heated to a higher degree than the larger portions of the contacting material through which the current passes whereby in each individual particle a condition may be induced whereby nitrogen may be absorbed at one point and delivered to a ,hydrogeniat another throughout the porous mass simultaneously whereby a mixture of nitrogen and hydrogen may be supplied simultaneously and continuously and the ammonia produced or discharged,

instead of supplying the gases alternately and directl altering or changing the temperature o the catalytic or contact metal 1:

cal-bid directly or by or through the means whereby such heat is induced such as electricity. p

Referring to the ap aratus as illustrated in Figs. 1 and 2 empoyed in the production-of ammonia from nitrogen and hydro g'envemploying the calcium ferricarbids or its vequivalent the operation is carried out as follows: The calcium-iron carbid catalytic or contact substance in a broken or granulated condition is supplied to the apparatus'upon the arch support 6 at 13 in such volume as to cover the contact rods or electrical conductors 1'2 and fill the compartinentsevenly throughout and at a height of about one-half the distance between the bridge support and the top of the lining 2. The apparatus is then closed by securing the flanges of the cover and furnace by means of the bolts 4. A current of elecc tricity is then passed through the apparatus by means of the leads 12 between the contacts 8 and 9 and through the conductors 10 and 11 whereby the carbid catalytic material. becomes heated and when sufficiently hot to admit of the absorption or combination of nitrogen therewith which can be indicated by the pyrometer 23, nitrogen is introduced through the supply pipesl4 by opening the valve 19 which passes into the apparatus and becomes compressed therein passing up throu [1 the openings 7 in con-- tact with the' car id 13, until it shall have reached a pressure sufiicient to be dischar ed through the adjusted and weighted re ief valve 21., The nitrogen then becomes absorbed by the carbid up to'a desired degree of saturation when the current density of the heating current is altered and the nitrogen supply out 01f by closing the valves 19. Hydrogen is then admitted through the inlet 15 by opening'the valve 18 whereupon the nitrogen is abstracted from the carbid and combined therewith passing out through the discharge conduit 20 to relief valve 21 and conduit 22 to a point where the same is recovered or se cHredT' Referring to Figs. 3 and 4, the number 25 designates the shell or outside retaining wall of thef-urnace, provided with the lining 26.-

The shell 25 is provided with the cover 27 secured thereto by means of bolts 28 passing through the flanges 29, the said cover being provided with openings 30 for the discharge fine 31,. Within and passing-through the furnace is the retort 32 provided with the heads 33 and 34, respectively. The head 33 being provided with the inlets 35 and 36 controlled by the valves 37 and 38 respectively of nitrogen N and hydrogen H, While the'hea'd34 is provided with outlet 39 controlled by the adjustable .relief valve 40 and the conduit 41. The retort 32 is supportedon the brick supports 42 in such' a manner that the combusting gases may circulate about the 'retort between the openings 43 between them and these spaces below the retort together with arch space 44 provides a suitable combustion chamber for the combusting gases. On either side of the furnace is provided the inlets 45 and 46 for the combustible gases and air which are supplied through the air supply pipes A and the gas supply pipes G controlled by the respective valves 47 and 48, respectively. The heads of the retort 49 being secured thereto in a removable manner by suitable means such as the screw clamp device 50. The interior of the retort being partly filled with the carbid catalytic agent 51. Thecombustion chamber 44 is provided with a communicating pyrometer 52 whereby-the temperature of the ingredients-in retort 32 may. be 'esti-- mated or ascertained. The combustion chamber is provided with a means whereby the combustion gases may be ignited, such as the openings 53 and 54' at either end of the furnace, said openings beingprovided with the swinging closures 55 and 56, respectively, through which,'- when opened, a

lighted taper or other igniting device may be introduced so as to communicate in an ignitable manner with the combustion gases and air introduced through the supply conduits or pipes 46.

The operation of the combustion heated i apparatus is similar to that of the electrically heated. Calcium or other iron car- 'bid is placed in retort 32at 51 and the heads 3.3 and 34 closed by the closures 49 actuated by the screw clamp securing device 50. The retort is then heated by means of the combustion of gas entering through theipalve controlled gas conduit Gr mixed with aur from supply conduit A and ignited in the furnace through the openings 53 and 54, the combustion in the space 44 about the retort 32 heats the retort and when at the proper temperature, selective to the carbid employed to take on nitrogen which may he l I I.

the formation of ammonla.

ascertained by the pyrometer 52, nitrogen is introduced into the retort by opening the valves 37 controlling the nitrogen conduit 35 whereupon the nitrogen enters and is ab-, sorbed by the carbid. When the carbidhas been properly saturated with nitrogen, the

' supply of nitrogen is cut off by closing valve 37 and the temperature is changed to a! point Where its affinity is reduced and hy'; drogen introduced through pipes 36 by open,- #5 ing the valve 38, whereupon the hydrogen-.5] seizes the nitrogen forming ammonia and is. discharged from the apparatus through thei'f, relief valve 40 and conduit 41 and suitably secured therefrom. In some cases as here-'36) inbefore noted, the combustion, orthe heat-, ing current of electricity may be regulated to such a nicety that the hydrogen and'nitrog gen may be simultaneously admitted 'and'if the ammonia produced, discharged or with.- as

, drawn continuously. It is also found ad-j f visable in some cases to preheat either the S nitrogen or hydrogen or both before intro;

'duction into the reaction or. combiningi'j chamber where the cooling action of the 'feo gases compared with the volume supplied and the capacity of the apparatus is con? cerned. hen electricity is employed as means for actuating the heat throughout the. body or mass of metal carbid contact mate- 055 rial, it may be of alternating, po'lyphase, direct or other character without departing from the spirit of the invention so long as it coacts with the ingredients to bring about 7 the conditions necessary for the union or.100 combination of nitrogen and, hydrogen in This process is based upon the fact that certain solid metal carbids, such as calciumcarbid, iron carbid, and the like, have an affinity for nitrogen when heated and exposed to tlie action'of nitrogen and at certain selective temperatures take on the same forming solid compounds therewith 'andat certain other temperatures the aflinity of the metal base of the carbid for carbon is s changed or intensified that such nitrogen as I may be received or absorbed in the first instance .mayw be delivered to a substance capable of combining therewith. such as hy- I s drogen and the nitrogen recovered there-- fronrin nascent form capable of unitingwith the hydrogen. The present invention? therefore contemplates the utilization of these properties of solid metal carbids for-130 the securing ofnitrogen and fixation of the same to and with hydrogen 1n a progressive or continuous manner and thereby produciii ig a cumulative yield of annnonia-which I can be absorbed in water, compressed to liquid, combined with other elements, forming compounds, compositions or substitution products, or with acids to form salts or compounds or united in otl erforms of ammoniacal or azoical compoi ds or compositions. ".0

The reactions which take place during the employment of'calcium iron carbid in the transformation into nitrogen compounds therewith and delivery of the same to hydrogen in the presence of hydrogen may be illustrated by the following chemical formula or equations: The coked mixture or combination of calcium carbid and iron carbid in the preferred proportions employed may be considered as illustrated by the formula Ga FeC 2OaC +FeC Ca FcC Union of nitrogen:

2CaU +FeC +6N:Ca Fe (CN) Formation of ammonia:

Qa Fe (UN) ,}-18I'I:: Cla FeO +6NH It will be noted that the solid carbid catalyst is used over and-over again with little loss.

The nitrogen may be obtained by passing air over BaO producing barium peroxid BaO -by absorbing-of oxygen and the only gen obtained therefrom by reducing the pressure and elevating the temperature thereof by what isknown as the Brin process and the hydrogen may be supplied as Water gas or such hydrogen from which thecarbon oxide may; have been separated.

The term containing car-bid, employed herein is intended toimply and does imply a carbid as such per 8c orassociated with other specific carbide or substances, such for instance as carbon employed as a hinder or surface augmenting vehicle or earlier.

The altering of the temperature to augment the seizing of the nitrogen and delivery of the same to hydrogenmay beprogres sively from lower to higher or higher to lower as the case may be with relation to the character of the carbid employed as to whether its afiinity for nitrogen increases and decreases in either direction.

It is olwi'ous that when the hydrogen employed is-amociated with other substances,

such as carbon monoxid or carbon dioxid or both, as may be the case in so-called wa:

ter gas, that 'more or less of the ammonia produced will be combined or united in the form of formate or carbonate. The ammonia produced may be combined with acids to form sulfate or chlorid, absorbed in water, compressed to liquid form or otherwise I secured.

.l.he terms progressive and progresssively employed herein in reference to the continuation or carrying on of the process and with reference ti) stepsv entering into the change in temperature and the relative change in affinities of ingredients and the character of reacting agents supplied is intended to imply and does imply the con tinuous carrying on of the-various steps em;

ployed during the progress or continuance of the process.

Having now described my invention What I claim as new and desire to secure by Let- 2. The process of making ammonia, which comprises heating solidmetal carbidand exposing it to the action of nitrogen and hydrogen under alternately higher and lower temperatures which diflersufiiciently to materially vary the ailinity of the carbid for nitrogen.

The process of'making ammonia, which comprises internally heating a substance,

containing calcium carbid under conditions which alternately vary the ailinity of such substance-for nitrogen, and exposing it to the'alternate action of nitrogen and hydrogen While under superatmospheric pressure.

4. The process of making ammonia, which comprises internally heating a substance containing calcium-carbid, and exposing it to the action of nitrogen and hydrogen un-' der alternately higher and lower tempera tures which difi'er sii'fiicintly to materially alter the aflinity of said substance fornitro' gen while under superatmospheric prewar-e.

-5. The process of making ammonia, which comprises heatin'gsolid metal carbid and exposing it to the action of nitrogen'and hydrogen. under temperatures which differ suiliciently to cause a material .variation in the affinity ofthe carbid for nitrogen.

6. The process of making ammonia, which comprises heating solid metalcarbid and exposing it to the alternating action of nitro gen and hydrogen while under superatmos pheric pressure and under conditionswhich 'vary the affinity of the carbid for nitrogen. '7. The process of making ammonia, which comprises heating solid metal carbid and exposing it to the action of nitrogen and hy drogen under alternately higher and lower temperatures which differ sufficiently to ma- L terially vary the 'afiinity of the car-bid for nitrogen and while under superatmospheric pressure.

8, Theprocess of making ammonia, which comprises. internally heating a substance containing calcium carbid, and exposing it to the action of nitrogen and hydrogen under temperatures which differ sufiiciently to materially vary the affinity of said substance for nitrogen, and under superatmospheric pressure. v

9. The process of making ammonia, which comprises heating a substance containing calcium carbid until it has reached a temperature at which it has an affinity for nitrogen. supplying nitrogen thereto, altering the temperature of the substance until it has a less atlinity for nitrogen, and removing nitrogen from said substance by subjecting the same to the action of hydrogen.

10. The process of makingammonia, which comprises heating solid metal earhid and exposing it to the action of nitrogen and hytemperature is reached at which the carbidhas less allinity for nitrogen and has an allinity for hydrogen. removing the. nitrogen therefrom by subjecting the ingredients to the. action of hydrogen, and remoi'ing the hyd ogen absorbed or occluded by exposing the substance to the action of nitrogen while reached a at the same temperature at which the substance has an allinity for nitrogen.

12. The process of making ammonia which eomprises heating metal carbid until it has temperature at which ithas an aflinity for nitrogen. supplying nitrogen thereto. (hanging the temperature until a temperatureie; reached at which the carbid has less aflinity for nitrogen and has an afiinity for hydrogen, removing the .nitrogen therefrom by subjecting the ingredients to the action of hydrogen, and removing the hydrogen absorbed or occluded by exposing the substance to the action of nitrogen while at the same temperature at which the sub stance has an allinity for nitrogen and while under-superatniospherie pressure.

In testimony whereof. I ailix my signature in' the presenve of two witnesses.

\Yitnesses:

U. G. GER)", F. I). Ylniitn. 

